/*
 This source file is part of the Swift.org open source project

 Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
 Licensed under Apache License v2.0 with Runtime Library Exception

 See http://swift.org/LICENSE.txt for license information
 See http://swift.org/CONTRIBUTORS.txt for Swift project authors
*/

import PackageModel

extension PackageDependency {
    /// Create the package reference object for the dependency.
    public func createPackageRef() -> PackageReference {
        // TODO (next steps): move the location into PackageKind to preserve path vs. location
        let packageKind: PackageReference.Kind
        switch self {
        case .fileSystem(let settings):
            packageKind = .fileSystem(settings.path)
        case .sourceControl(let settings):
            switch settings.location {
            case .local(let path):
                packageKind = .localSourceControl(path)
            case .remote(let url):
                packageKind = .remoteSourceControl(url)
            }
        case .registry:
            // FIXME
            fatalError("registry based dependencies not implemented yet")
        }
        return PackageReference(identity: self.identity, kind: packageKind)
    }
}

extension Manifest {
    /// Constructs constraints of the dependencies in the raw package.
    public func dependencyConstraints(productFilter: ProductFilter) throws -> [PackageContainerConstraint] {
        return try dependenciesRequired(for: productFilter).map({
            return PackageContainerConstraint(
                package: $0.createPackageRef(),
                requirement: try $0.toConstraintRequirement(),
                products: $0.productFilter)
        })
    }
}

extension PackageContainerConstraint {
    /// Constructs a structure of dependency nodes in a package.
    /// - returns: An array of ``DependencyResolutionNode``
    internal func nodes() -> [DependencyResolutionNode] {
        switch products {
        case .everything:
            return [.root(package: self.package)]
        case .specific:
            switch products {
            case .everything:
                assertionFailure("Attempted to enumerate a root package’s product filter; root packages have no filter.")
                return []
            case .specific(let set):
                if set.isEmpty { // Pointing at the package without a particular product.
                    return [.empty(package: self.package)]
                } else {
                    return set.sorted().map { .product($0, package: self.package) }
                }
            }
        }
    }
}
